A: What type of tree is that?
B: I think it is an oak tree. It is certainly large enough to be one.
oak
n. １．櫟樹，橡樹；２．櫟木，橡木
A: Oh no, I’ve dropped an oar .
B: We will have to swim to the shore now.
oar
n.　槳，櫓
A: Please tell me the big secret.
B: Sorry, I took an oath and swore that I wouldn't.
oath
n.　１．誓言，誓約；咒罵，詛咒語
on / under oath　 在法庭上宣過誓
A: My pupils are so obedient , they always do their home work.
B: You are lucky, mine are terrible.
obedient
a.　服從的，順從的
A: Robert told an obscene joke last night.
B: Is it too rude to repeat to me?
obscene
a.　１．淫穢的，下流的；２．可憎的，可惡的
A: Did you understand the theatre performance?
B: No, it was too obscure for me.
obscure
a.　１．不著名的，不重要的；２．費解的，模糊不清的；３．隱藏的，偏僻的
vt.　使變模糊，掩蓋
A: You are always playing video games.
B: I know. I have an obsession.
obsession
n.　困擾，無法擺脫的思想（或情感）
A: Excuse me, but your car is obstructing the entrance to my home.
B: Oh, I’ll move it right away.
obstruct
vt.　１．阻塞，堵塞；２．阻礙，阻止，妨礙
A: Can I move into the apartment today?
B: No, you can have occupancy next week.
occupancy
n.　占有，使用，居住
A: What is that terrible odour ?
B: Oh, sorry, it must be my socks.
odour
n.　氣味
A: Beverley looked stunning at the party.
B: Yes, her outfit was offset by her jewelry.
offset
vt.　補償，抵消
A: Do you have any offspring ?
B: Yes, I have three daughters.
offspring
n.　１．子女，子孫，后代；２．（動物的）崽
A: Do you like olives ?
B: Yes, especially black ones in salad.
olive
n.　橄欖，橄欖樹
A: Is that glass clear?
B: No, it is opaque , that is why you are having difficulty seeing through it.
opaque
a.　１．不透明的，不透光的；２．難理解的，晦澀的
A: Women in the old days were frequently oppressed by their husbands.
B: I am glad that times are changing.
oppress
vt.　１．壓迫，壓制；２．使（心情等）沉重，使煩惱
A: You would like the blue car?
B: No, I think I’ll opt for the red one.
opt
vt. (for)　選擇，挑選
A: The weather will be wonderful tomorrow.
B: You are always filled with optimism .
optimism
n.　樂觀，樂觀主義
A: I study at my optimum between eight and ten in the morning.
B: Oh, I work best in the evenings.
optimum
a.　最合適的，最優的，最佳的
A: Where did you get the apples?
B: I picked them in the orchard down the road.
orchard
n.　果園
A: I was in a serious car accident last year.
B: That must have been a terrible ordeal .
ordeal
n.　苦難經理，折磨，煎熬
A: I love studying science.
B: I orient more towards the Arts.
orient
vt.　１．使適應，使熟悉情況（或環境等）；２．（to ,toward）使朝向，以．．．為方向（目標）
n.　東方，亞洲（尤指遠東），東半球
A: Oriental cuisine is my favourite.
B: Yes, I also love Chinese food.
oriental
a. 東方的，東方人的，東方文化的
A: I was unable to find my orientation in the city.
B: You should have carried a map with you.
orientation
n.　１．方向，目標，方位；２．熟悉情況，適應，情況介紹
A: From where does the guitar originate ?
B: Well, there are many types of guitar, so probably many countries.
originate
vi. (in,from,with)　起源于，來自，產生
vt.　創造，創始，開創
A: That is a beautiful ornament beside the TV.
B: Thanks, it was a gift from a friend.
ornament
n.　１．裝飾品，點綴品；２．裝飾，點綴
vt.　裝飾，點綴，美化
A: I was an orphan until the age of seven.
B: Goodness, do you know what happened to your parents?
orphan